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From: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
To: zhoumin <teczm@foxmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] fat: Optimized FAT bad char check
Date: Thu, 10 Apr 2025 22:44:41 +0900	[thread overview]
Message-ID: <874iyw6shi.fsf@mail.parknet.co.jp> (raw)
In-Reply-To: <tencent_4E3BCCDC793A514260932AA16BC5910F400A@qq.com>

zhoumin <teczm@foxmail.com> writes:

> Hi Hirofumi
>
>> Why do you need this change?
>
> I encountered an issue while working on our own bootloader. The problem
> occurs when short file names start with `0`. In this case, our bootloader
> mistakenly interprets it as the end of the directory entry, causing all
> subsequent files in the directory to become invisible.

It is normal behavior of Windows.

> While comparing our bootloader with the kernel, I found this bad char check
> function. Treating the `0x05` deleted flag as a bad character may
> potentially disrupt the parsing chain for subsequent files.
>
> In my opinion, adding this judgment aligns with the spec and should not
> introduce any negative side effects, even though I haven’t encountered this
> situation in practice.

What specific case are you saying?  This path is checking the user
input, isn't it? Why do you allow to create that filename includes 0 or 5?

Looks like you are overlooking something.

Thanks.
-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>

  reply	other threads:[~2025-04-10 13:44 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-09 17:27 zhoumin
2025-04-09 18:52 ` OGAWA Hirofumi
2025-04-10 13:07   ` zhoumin
2025-04-10 13:44     ` OGAWA Hirofumi [this message]
2025-04-10 14:28       ` zhoumin

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